A view of the gun salute at The Tower of London before the funeral service of Britain's Prince Philip, in London, Britain April 17, 2021. Cpl Ed Wright RAF/UK MOD Crown Copyright 2021/Handout via REUTERS

Camilla, Duchess of Cornwall, meets Brigadier Phil Prosser during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Natasha McEnroe, keeper of medicine at the Science Museum, shows to Britain's Prince Charles the first vials of the Pfizer-BioNTech and Oxford/Astra Zeneca COVID-19 vaccines during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles, Camilla, Duchess of Cornwall, NHS England National Medical Director Stephen Powis and Chief Executive of the National Health Service in England Sir Simon Stevens are pictured during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles visits the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles watches a promotional video feature actor Sir Michael Cane during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Camilla, Duchess of Cornwall, is pictured next to Amanda Pritchard, Chief Operating Officer at NHS England, during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles, Camilla, Duchess of Cornwall, speaks to Chief Nursing Officer for England Ruth May during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles, Camilla, Duchess of Cornwall, and Chief Executive of the National Health Service in England Sir Simon Steven are pictured during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles talks during a visit at the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles visits the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Camilla, Duchess of Cornwall, visits the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

Britain's Prince Charles visits the Skipton House to meet NHS and MOD staff involved in the vaccine rollout, amid the coronavirus disease (COVID-19) pandemic, in London, Britain March 9, 2021. Aaron Chown/Pool via REUTERS

A demonstrator holds a regulated box mod during a protest at the Massachusetts State House against the state’s four-month ban of all vaping product sales in Boston, Massachusetts, U.S., October 3, 2019. REUTERS/Brian Snyder

Britain's Secretary of State for Defence, Gavin Williamson, shakes hands with U.S. Secretary for Defense, Jim Mattis, at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson sits opposite U.S. Secretary for Defense, Jim Mattis, before a meeting at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

U.S. Secretary for Defense, Jim Mattis, sits opposite Britain's Secretary of State for Defence, Gavin Williamson, before a meeting at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson sits opposite U.S. Secretary for Defense, Jim Mattis, before a meeting at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson (back to camera), and U.S. Secretary for Defense, Jim Mattis, sit opposite each other before a meeting at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson, and U.S. Secretary for Defense, Jim Mattis, talk before a meeting at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson, and U.S. Secretary for Defense, Jim Mattis, talk before a meeting at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson, shakes hands with U.S. Secretary for Defense, Jim Mattis, at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

Britain's Secretary of State for Defence, Gavin Williamson, shakes hands with U.S. Secretary for Defense, Jim Mattis, at the Ministry of Defence (MoD) in central London, Britain November 10, 2017. REUTERS/Simon Dawson

One of the first customers, Mod, 22 of Bangkok poses with his iPhone X during its launch at the Apple store in Singapore November 3, 2017. REUTERS/Edgar Su

First customers to buy iPhone X Kittiwat Wang, 22, and Mod, 22, of Bangkok pose with their iPhone X at the Apple store in Singapore November 3, 2017. REUTERS/Edgar Su

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville TPX IMAGES OF THE DAY

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Defence Secretary, Michael Fallon, speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Prince Harry speaks at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Britain's Prince Harry is greeted by Defence Secretary, Michael Fallon and the Chair of the Royal Foundation, Keith Mills, as he arrives to speak at an event on mental health, at the Ministry of Defence (MoD), in central London, Britain October 9, 2017. REUTERS/Toby Melville

Two 'mods' sit on their scooters as visitors, mainly dressed in period costume, attend the Goodwood Revival festival, celebrating the halcyon days of British motor racing, at Goodwood race circuit in south England, September 8, 2017. REUTERS/Toby Melville TPX IMAGES OF THE DAY

Two 'mods' sit on their scooters as visitors, mainly dressed in period costume, attend the Goodwood Revival festival, celebrating the halcyon days of British motor racing, at Goodwood race circuit in south England, September 8, 2017. REUTERS/Toby Melville

Two 'mods' sit on their scooters as visitors, mainly dressed in period costume, attend the Goodwood Revival festival, celebrating the halcyon days of British motor racing, at Goodwood race circuit in south England, September 8, 2017. REUTERS/Toby Melville

Vape Mods are seen at a stand during the Vape Trade Convention (VTC) in Mexico City, Mexico, June 11, 2017. Picture taken June 11, 2017. REUTERS/Victor Ruiz Garcia

A bird bathes in a mod puddle as a plastic bag is seen side of a road on a wet day in Colombo, Sri Lanka June 7, 2017. REUTERS/Dinuka Liyanawatte TPX IMAGES OF THE DAY

A bird bathes in a mod puddle as a plastic bag is seen side of a road on a wet day in Colombo, Sri Lanka June 7, 2017. REUTERS/Dinuka Liyanawatte

India's Prime Minister Narendra Modi (L), President Pranab Mukherjee (C), Lok Sabha speaker Sumitra Mahajan (2nd R) and Vice President Mohammad Hamid Ansari (R) walk inside the parliament premises as they arrive to attend the first day of the budget session, in New Delhi, India, January 31, 2017. REUTERS/Adnan Abidi

View of Afghanistan's Ministry of Defence (MOD) in Kabul, Afghanistan, February 7, 2016. Picture taken February 7, 2016. AfghanistanLM REUTERS/Omar Sobhani

Martin Heath, a Mod and fan of the group 'The Jam', gestures after arriving by scooter in the courtyard of Somerset House in London, Britain August 22, 2015. Somerset House is hosting the exhibition 'The Jam: About the Young Idea' . REUTERS/Peter Nicholls

Mods riding 60's era looking scooters arrive in the courtyard of Somerset House in London, Britain August 22, 2015. Somerset House is hosting the exhibition 'The Jam: About the Young Idea' . REUTERS/Peter Nicholls

Martin Heath, a Mod and fan of the group 'The Jam', sits on his scooter in the courtyard of Somerset House in London, Britain August 22, 2015. Somerset House is hosting the exhibition 'The Jam: About the Young Idea' . REUTERS/Peter Nicholls

Martin Heath, a Mod and fan of the group 'The Jam', sits on his scooter in the courtyard of Somerset House in London, Britain August 22, 2015. Somerset House is hosting the exhibition 'The Jam: About the Young Idea' . REUTERS/Peter Nicholls

Martin Heath, a Mod and fan of the group 'The Jam', sits on his scooter in the courtyard of Somerset House in London, Britain August 22, 2015. Somerset House is hosting the exhibition 'The Jam: About the Young Idea' . REUTERS/Peter Nicholls

Mods riding 60's era looking scooters arrive in the courtyard of Somerset House in London, Britain August 22, 2015. Somerset House is hosting the exhibition 'The Jam: About the Young Idea' . REUTERS/Peter Nicholls

A security agent carries a statuette of Mahatma Gandhi, given by a person in the crowd of onlookers to India's Prime Minister Narendra Modi (not pictured) as Modi arrives to pay homage at the full-sized Ghandi statue in front of the Indian Embassy in Washington September 30, 2014. U.S. President Barack Obama and Modi vowed on Monday to expand and deepen their countries' strategic partnership and make it a model for the rest of the world. REUTERS/Jonathan Ernst (UNITED STATES - Tags: POLITICS)

Designer Lupe Andrade (R) of Winnetka, California puts the final touches on her creation worn by model Rosalie Burke named 'Elizabeth' during the 10th annual toilet paper wedding dress contest in Midtown, New York June 12, 2014. The materials used to make the dress include 12 rolls of Charmin Ultra Strong, hot glue, mod podge glue, clear tape and thread. There was something old, something new, something borrowed and something double-ply for 10 designers who battled it out on Thursday for $10,000 and the top prize in the 10th annual toilet paper wedding dress contest held in New York City. REUTERS/Adrees Latif (UNITED STATES - Tags: ENTERTAINMENT FASHION SOCIETY TPX IMAGES OF THE DAY)

Designer Lupe Andrade of Winnetka, California puts the final touches on her creation worn by model Rosalie Burke named 'Elizabeth' ahead of the 10th annual toilet paper wedding dress contest in Midtown, New York June 12, 2014. The materials used to make the dress include 12 rolls of Charmin Ultra Strong, hot glue, mod podge glue, clear tape and thread. There was something old, something new, something borrowed and something double-ply for 10 designers who battled it out on Thursday for $10,000 and the top prize in the 10th annual toilet paper wedding dress contest held in New York City. REUTERS/Adrees Latif (UNITED STATES - Tags: ENTERTAINMENT FASHION SOCIETY)

Senator Elizabeth Warren tours the Alcator C-Mod experiment with MIT researchers to celebrate the restoration of funds to the program at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION POLITICS)

Research equipment for the Alcator C-Mod experiment is seen at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION)

Senator Elizabeth Warren tours the Alcator C-Mod experiment with MIT researchers to celebrate the restoration of funds to the program at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION POLITICS)

Senator Elizabeth Warren tours the Alcator C-Mod experiment with MIT researchers to celebrate the restoration of funds to the program at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION POLITICS)

Technicians monitor the Alcator C-Mod experiment at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION)

An engineer checks the monitors for the Alcator C-Mod experiment at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION)

(L-R) U.S. Senator Elizabeth Warren, MIT Vice President of Research Maria Zuber, MIT Professor Anne White, and U.S. Representative Katherine Clark react after initiating the start sequece on the Alcator C-Mod experiment at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION POLITICS)

(L-R) U.S. Senator Elizabeth Warren, MIT Vice President of Research Maria Zuber, MIT Professor Anne White, and U.S. Representative Katherine Clark wait out the countdown after initiating the start sequence on the Alcator C-Mod experiment at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION POLITICS)

Senator Elizabeth Warren (L) joins MIT Vice President of Research Maria Zuber (C) and U.S. Representative Katherine Clark as they initiate a start sequence on the Alcator C-Mod experiment at the MIT Plasma Science and Fusion Center in Cambridge, Massachusetts, February 24, 2014. The experiment is one of three fusion research operations in the nation, and was set to be dismantled last year as part of the sequester budget cuts. REUTERS/Dominick Reuter (UNITED STATES - Tags: SCIENCE TECHNOLOGY EDUCATION POLITICS)